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The purpose of the lab is to generate a watershed sediment transport index value and compare to previously published values. Channel stability: “is the ability of a stream
First step is to generate the watershed using the DEM downloaded from Michigan CGI. Next Extract the watershed extent from the flow accumulation surface using the Spatial Analyst Tools/Extraction/Extraction by Mask. The mask data is the watershed you delineated.
Once the DEM is clipped to the extent of the watershed, run the slope tool and get the slope of the watershed. Finally, run the sediment transport formula in the raster calculator. The syntax is:
Power(“FlowAccumulationArea”/22.13,0.6) * Power(Sin(“Slope_Extrac1”/0.0896),1.3)
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Hello!
ReplyDeleteThank you for your interesting post.
I have a strange problem I don't understand concerning the STI.
When I apply your formula given above in the raster calculator, the resulting raster shows randomly pixels with no data, while other pixels have been calculated correctly.
My slope and flowaccumulation raster are consistend and give values for each cell. In my opinion the raster calculator shouldn't pretend that for some of the cells the equation has no solution; which it does by stating "no data".
Do you have an idea what might be the problem?
Thanks in advance